NASA said an unexpected reading in a ground control interface with the launcher prompted the postponement, initially for 24 hours and then until tomorrow at 1009 GMT.

"Engineers from NASA and Orbital Sciences Corp. continue to troubleshoot a technical issue that arose during yesterday's initial launch attempt," the space agency said in a statement.

"The target launch date also will ensure personnel get the required rest before entering another countdown," it added.

Data from the Glory mission will allow scientists to better understand how the sun and tiny atmospheric particles called "aerosols" affect Earth's climate and how they may affect human life.